About this time every year, people ask Jay Portnoy whether this is the worst allergy season ever.
And every year, Portnoy, director of the allergy division at Children’s Mercy Hospital, answers: “It probably is.”
The sneezes and itchy eyes we’re contending with mark the start of a mighty tree pollen season, Portnoy said Monday. Right now, the juniper and elm are pollinating. Maples and ash will be next. And later, oaks and walnuts.
“So far, for juniper, it’s pretty robust,” Portnoy said. “If it’s not the worst season on record, it’s pretty close.”
For the past 18 years, Portnoy and his Children’s Mercy colleagues have been taking pollen readings from instruments on the hospital’s roof. At first, pollen counts over 1,000 were unusual, but the numbers have been going up steadily over the years, a result of longer and more abundant growing seasons fueled by climate change’s higher temperatures and rising levels of carbon dioxide in the atmosphere.
Now, during pollen seasons, counts in the 1,000s are becoming the norm, Portnoy said.
Late last week, the pollen count hit about 5,000.
“That’s ridiculous,” Portnoy said.
Pollen counts didn’t rise any higher than about 4,000 over the weekend. And on Monday, the count was down to 838. But even pollen counts of 100 or less can trigger allergic symptoms, Portnoy said.
A rain, such as the one predicted for Tuesday, could wash the pollen out of the air for a short time, Portnoy said. But the pollen will inevitably return.
A hard freeze can shut down pollen production for several weeks, Portnoy said. But the freezing temperatures predicted for later this week are “probably not low enough or long enough to be a problem for the trees.”
If you haven’t been smacked by the tree pollen, just keep in mind: We still have to contend with grass pollen in May and June and then ragweed season beginning in mid-August.
Portnoy and other Children’s Mercy researchers have documented from their daily pollen counts that the total amounts of ragweed pollen collected annually have been two to three times higher in recent years than they were in the late 1990s. Ragweed pollen seasons also have been running longer, often extending into late October or even mid-November when they used to end by mid-October.
And USDA researchers have found that atmospheres with high carbon dioxide, such as those found in urban areas, not only produce more pollen, but the pollen is more potent at triggering allergic reactions.
Portnoy said he suspects that the tree pollen we’re contending with now also is more potent than it was in the past.